This specification generally relates to speech recognition systems.
With the development of mobile devices, some speech-related technologies are becoming popular. For example, search by voice services may utilize speech recognition to interact with mobile devices. Some existing keyword spotting (KWS) systems on mobile devices use deep neural networks (DNN), which are trained to predict sub-keyword targets. For instance, DNNs may be used for keyword spotting since DNN models may be adjusted by changing the number of parameters in the networks.